没有返回键破坏活动？ [英] Did back key destroy an activity?

问题描述

我有定义如下活动：

    <activity android:name="com.example.ui.HomeActivity"
        android:alwaysRetainTaskState="true"/>

一个很奇怪的是，在模拟器上运行时，和返回键是pressed，该活动被破坏（我看到的onDestroy（）调用日志）。但我的Nexus One手机上运行时，和返回键是pressed，该活动不被破坏（我没看到的onDestroy（）调用日志）。

A strange thing is that, when running on emulator, and the back key is pressed, the activity was destroyed (I saw onDestroy() called in log). But when running on my Nexus One phone, and the back key is pressed, the activity is not destroyed (I didn't see onDestroy() called in log).

有人能告诉我为什么吗？

Could someone tell me why?

感谢。

推荐答案

在活动是在后台（后pressing后退键）它总是停止，但系统还可以决定摧毁它（例如，当系统资源低）。你无法确定何时将被销毁。

When activity is in the background (after pressing Back key) it is always stopped but System can also decide to destroy it (eg. when system resources are low). You can't determine when it will be destroyed.

活动还可以通过调用完成销毁（） 。您可以确定通过检查 isFinishing（）在的onPause 或的的onStop 回调。

Activity can also be destroyed by calling finish(). You can determine that by checking isFinishing() status in onPause or onStop callback.

不要在的onDestroy回调不算数。如果系统会杀死活性它不会被调用。

Do not count on onDestroy callback. If system will kill activity it wont be called.

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